


Works

by stolashoots



Category: Undertale (Video Game)
Genre: Angst, Fluff, M/M
Language: English
Status: Completed
Published: 2015-11-24
Updated: 2015-12-09
Packaged: 2018-05-03 05:02:14
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 7
Words: 3,497
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5277677
Author URL: https://archiveofourown.org/users/stolashoots/pseuds/stolashoots
Summary: <blockquote class="userstuff">
              <p>A collection of drabbles already posted on tumblr.<br/>Additional warnings will be in the notes at the start of each chapter.</p>
            </blockquote>





	1. one.

**Author's Note:**

> Tumblr is a void and I need a better way of keeping track of things.
> 
> No warnings for this one.

Across the table, Gaster catches Sans’ eye as the skeleton attempts to stifle a yawn. “BORED?” He signs, glancing around to see if anyone has noticed. No one does, of course, just about every monster in the room is facing the presentation in the front, and they’re sitting near the back.

“YEAH, A LITTLE,” Sans replies after a moment, his fingers slow to form the letters. He’s still new at Wingdings, but it’s a talent he takes pride in. “I DON’T GET WHY WE HAVE TO BE HERE, THIS HAS NOTHING TO DO WITH US.” He gestures to their colleague presenting data on weather cycles. “WE DON’T EVEN GET WEATHER IN THE UNDERGROUND.”

“DRASTIC FLUCTUATIONS IN TEMPERATRE COULD POTENTIALLY CAUSE A MALFUCTION IN MACHERNERY AT THE LABS.” Gaster flitters out immediately, then settles down. They both turn to see a bar graph showing a steady growth. “THIS DOES NOT INVOLVE US DIRECTLY,” he admits grudgingly. He had attempted to keep a positive mindset regarding this meeting and forget that they were wasting valuable work hours, but Sans brings up a good point.

“IF IT WAS REALLY SERIOUS, THEY’D TELL US TO DO SOMETHING ABOUT IT, NOT WORRY THE KING ABOUT IT. I BET THEY DIDN’T HAVE ANYTHING GOOD TO PRESENT, SO THIS IS WHAT THEY CHOSE TO TALK ABOUT.” It takes a while for Sans to get the whole message out, and he makes a signal that tells Gaster he’s finished.

“REGARDLESS, THERE IS ANOTHER TWO HOURS TO GO BEFORE WE CAN GET BACK TO THE LAB. WE MIGHT AS WELL LISTEN RESPECTFULLY.” It’s meant to be a hint to Sans to act like he’s paying attention, but the skeleton just grins.

“NAH. HEY GASTER, YOU WANT TO LEAVE WORK EARLY AND GO SOMEWHERE?” Sans leans back in his chair, not even bothering to turn himself towards the front.

“…WHAT DO YOU HAVE IN MIND?”

“WHY, A DATE! I HAVE A DISCOUNT COUPON FOR GRILLBY’S AND THEY ALWAYS HAVE THE BEST KETCHUP! WE COULD CATCH A RIDE ON THE FERRY RIGHT AFTER THIS.” In his excitement, Sans throws his arms up in the air, gaining the attention of a few of their coworkers. Luckily, his arms are so short that most don’t notice.

“SANS, CALM DOWN, YOU’RE BEING DISTRACTING.”

“SO WHAT? IT’S NOT LIKE ANYONE ELSE KNOWS WHAT WE’RE SAYING.”

“YES, BUT-“ Gaster throws an apologetic smile to his neighbor.

“WE CAN GET NICE CREAM INSTEAD IF-“

King Asgore Dreemurr is sitting at the head of the table, only a few seats away from them. He leans forward and whispers, “Dr. Gaster, Dr. Sans, do I need to move you two?”

They both freeze in their antics, then look down, properly chastised. The King returns to his usual upright position, smiling at his two prized scientists. He holds out his hands and begins forming complex symbols, catching their attention. “YOU TWO HAVE FUN ON YOUR DATE,” he signs out with a wink.

Gaster promptly buries his face in his hands. Sans grins at the approval and gives the king a thumbs up.


	2. two.

**Notes for the Chapter:**

> This has implied nsfw, but nothing serious

Sans wakes to warm breath tickling the back of his neck and fingers delicately caressing his sternum. He shivers and peeks open an eye, checking the time on a nearby clock. 8 AM. “Don’t you have work?” He mumbles before burying his face into the pillow.

Behind him, Gaster gives a dismissive hum and slides his hands down to brush against Sans’ spinal column, taking a second to trace circles on each one. Sans arches into the touch, sighing as Gaster reaches his pelvic bone and holds him steady. Gaster nuzzles between his shoulder blades, then moves to nip and suck his shoulders. He nudges one of his legs in between Sans’ and grinds up against his symphysis pubis.

Sans moans, inadvertently throwing his head back, nearly clocking his lover in the face. “Mmm, come on Gaster, pick up the pace…”

With a mischievous grin, Gaster lets go of the pelvis, stroking his way back up the spine, and lands his hands on the sides of Sans’ rib cage. He flips them over, rolling on top of the other’s back. Gaster sits up and digs his fingers into Sans’ ribs, tickling him. The skeleton beneath him squirms and flails his arms, his laughter muffled by the pillow. He slaps a hand against Gaster’s femur to no avail, then bucks his hips up, successfully toppling his lover off. Instinctually, Sans pulls away from Gaster’s reaching grasp, only to roll off the bed.

Gaster peeks over the edge to look down on Sans. “MORNING LOVELY,” he signs.


	3. three.

**Notes for the Chapter:**

> Not really sanster, but it can be sort of implied??

Sans doesn't dare enter the Core anymore, but he's running out of steam and can't afford to waste magic jumping to the castle. With the main elevators shut down, there aren't many options left.

It is dark here, most of the power having been shut off, though a few of the lasers were left burning. The Core has always been a warm place, but goosebumps crawl up Sans' arms and there's a pricking sensation against the back of his neck. He's being watched.

The thought is absurd, everyone in the Underground has already either evacuated or died, and the place is completely empty. Even so, he can't shake the feeling.

A dark mass flickers into view in the corner of his eye, and he lurches around only to see... nothing? Yep, nothing, just a wall. Perfect.

He continues moving forward, this time ignoring the strange shapes on the edge of his vision. Sans' sure something is there, but it stays mostly out of view so he assumes it isn't threatening. It just happens to be going the same way as him. Not a problem.

It becomes a problem when something - it? - slams into his back, knocking him onto his hands and knees. His vision blurs and darkens for a second, and something slimy wraps around his ankle. A presence looms above him. Sans considers it menacing at first, but when it makes no move to hurt him any further, he breathes out and looks up.

It takes longer than he'll ever admit to recognize the mask-like face. It's distorted and warped, black sludge dripping out of the eye and mouth holes.

"Gaster," Sans asks because he isn't completely sure it's the same person. It smiles in confirmation and nods enthusiastically, shuffling even closer. Boney hands take hold of his shoulders and brings him to his feet. The monster is a lot shorter than he remembered, though it is so hunched over he could be wrong.

Sans looks for an escape route. Gaster’s hold on his ankle tightens. Shit.

"You're dead." He says because it's the truth.

"Soon you will be too." The voice comes from behind, smooth and low. Gaster's mouth moves with the words, but they don't exactly match up. Creepy, he thinks, but chooses not to voice out loud.

“That’s a depressing thought,” Sans isn’t sure if that is a threat or a warning, or even how much Gaster knows about the current situation. “I think I’d much rather stay on living.”

The creature’s smile falls. “The child won’t allow you to stand in their way. You will be killed instantly.” The statement is very matter of fact. He turns away for a second, “It is no matter. You will only be dead for minutes before everything resets.” Gaster has a distant look on his face, and his form wavers.

He’s fading fast, and the grip on his ankle slackens. “I’m not going to let that happen,” Sans says, because stopping the brat is the whole reason why he’s here.

“Perhaps,” the voice whispers into his ear, and he’s gone.

Sans whips around only to find himself alone again. He shakes his head, scolding himself for wasting time, and continues his way through the Core.


	4. four.

**Notes for the Chapter:**

> More implied stuff

Frisk pushes themself through the slimy reeds, not entirely positive what direction they’re heading in. The plants seem to stretch forever, and since it grows taller than them, it’s impossible to see their destination. In theory, they want to be leaving Waterfall, but at this point, they’d be ecstatic just to get out of this particular patch of swamp grass.

Just as the thought crosses their mind, they shove forward into the reeds and almost fall flat on their face when they’re met with no resistance. They’re agile enough to catch themselves before that happens and they quickly righten, glancing back and forth to see if any monsters noticed. They’re alone as always, though, so it’s a moot point.

They’ve marched right into a clearing surround by, what else, too tall grass. Luckily, someone thought to put a bench on the edge. Frisk sits down, sighing in relief at a chance to rest their tired limbs. It’s been a long day, and they fear it’s only going to continue to get longer. The climb up the mountain was strenuous enough, they hadn’t expected to have such a journey ahead of them when they started this.

They sigh again and roll their shoulders, pondering the proposition of backtracking and seeing if they could rest for a couple of hours at Papyrus’ house. They regret not renting at room at Snowdin’s inn, but it’s too late now. They just have to continue pushing on and hope this’ll all be over soon.

Frisk notices that one of their shoes is untied, and they bend down to fix it. “The little bunny goes over the hole and through it,” they think as they loop the strings and tie it.

“Forget me,” a voice whispers, startling Frisk. They jump to their feet and look around for the source, but no one is there.

“Please, forget me.” The voice sounds desperate, and for a moment, Frisk wants to ask who exactly they should be forgetting before realizing it isn’t a person or monster speaking. There must be a whisper flower nearby.

Frisk ducks down and, sure enough, a small one is growing under the bench. The flower shifts and says a mumbled word or two in a different voice.

“Forget me,” the first repeats again.

“Never.” This time Frisk can make out the second voice. It sounds familiar.

“The pain will go away once all memories of me vanish.”

“I don’t mind hurting.”

“It would be better for everyone.”

“Nothing’s ever easy with you.” There’s a sniffle immediately after this, most likely from the second voice. Was the owner crying? They sound almost defiant.

“Please forgive me.” The first voice is becoming difficult to hear, as though the owner is walking away.

“Always.”

“Then why won’t you let me go, Sans?”

“I love you, ******.”

Frisk’s blood runs cold. The voices end here, the flower drooping slightly, but they can’t help but feel dirty knowing they just witnessed such a private conversation, especially considering they know one of the participants.

They stand and back away, rapidly deciding that it’s time to leave. Frisk nearly sprints out of the clearing before realizing they should overwrite the whisper flower so no one else wanders along and hears it.

Frisk turns and heads back over to the bench and kneels down. Making sure the flower is listening, if a flower can even do that, they hum a little tune they picked up from Toriel. The flower begins repeating it as soon as they finish.

Frisk stands again and, with one last look at the bench, hurries off.


	5. tums

**Notes for the Chapter:**

> This felt really awk to write but Sans' tummy give me life.
> 
> All sign language is ASL that I found on signingsavvy.com

“Long day?” Gaster hears Sans calling from the living room. He sighs and steps out of the doorway, takes off his shoes, and sets his satchel down. He spies Sans lounging on the couch, not exactly watching the television. He nods and joins him, leaning back into the cushions.

“That bad, huh? Why not relax the rest of the day, I can make us dinner later.” Gaster gives him a doubtful look. “Okay, I can stop by Grillby’s and pick us up something fried and greasy.” Not exactly the healthy route, but it’s fine to indulge occasionally.

Speaking of indulging… Gaster shifts towards Sans, catching his attention immediately. He pokes his own stomach twice with his fingers together. _Belly_.

Sans grins, his eye lighting up, and Gaster shivers at the sensation of magic. Sans’ shirt fills, no longer empty, and the edges glow blue. He pulls it up to his ribs to show off his newly formed stomach. It’s not real of course, skeletons have a tendency to lack skin and other organs, but magic is a funny thing.

Gaster places his hand on his tummy, careful not to puncture the squishy structure. He’s learned from past experiences that pushing too hard is never good when it comes to Sans. As he caresses the pseudo skin, Sans turns to face him, sitting cross legged, and hums in content.

Gaster brings up his other hand to squeeze his side, then relaxes his grip when Sans tenses. He lets go and slides his hand across his belly, tapping a rhythm with his fingers.

His pitches forward and buries his face into the glowing stomach. He groans when Sans nudges his shoulder, laughing.

“So, I guess you don’t want that dinner?” Sans asks, amused. He reaches up to massage the back of Gaster’s skull. Gaster holds out a hand, his fingers together and thumb up, and pushes it forward.

_Later_.


	6. six.

**Notes for the Chapter:**

> Happy Thanksgiving to everyone who celebrates :3
> 
> Post-core

The darkness gathers over a sleeping figure, particles of energy merging together to form a single mass that wavers and flickers in and out of existence. As if sensing the disruption, the monster in the bed below groans and curls in on himself, bringing his blanket over his head and shuddering.

A nightmare, it seems, how unfortunate. He hadn’t planned on doing more than a quick visit, but seeing Sans in such a state certainly causes him pain. He has to concentrate but slowly, slowly, he’s able to force his body to solidify. Gravity takes a hold of him and he crashes to the floor.

Sans stiffens momentarily but is quick to relax. There is no movement from the other room. He staggers to his feet, unused to the feeling of actually having a physical form. It won’t last forever, he knows, and he only has the strength to hold it for so long before he’s forced to leave reality.

He leans over Sans and sets his hand on the bump he suspects is a skull. There is no reaction so he carefully tugs the blanket out of his clutches and sets it to the side. He pulls Sans out of his cramped position and lays him properly on his bed, his head actually making use of his pillow. The blanket is flattened out on top of him. There, that’s better. Sans actually looks comfortable now, and he’s no longer shaking.

He pats Sans’ head again, fully prepared to fade from existence as though he was never here, but Sans rolls to his side and murmurs, “Gaster…”

The being, Gaster, freezes, suddenly terrified he’s been spotted, but Sans’ eyes are closed and his breath is even. He hasn’t been caught, what a relief.

He can feel the edges of his form dissipating; he doesn’t have much time left. Gaster ducks down to plant a kiss on Sans’ forehead before allowing himself to go completely. In a matter of moments, any evidence of him ever being here has vanished.

As his essence tears and scatters itself though the universes, Gaster promises to one day return for good.


	7. things he misses

**Notes for the Chapter:**

> This is actually the second sanster piece I wrote, the first being the first chapter in this, but I couldn't figure out the ending so it's been sitting in a folder for a while haha
> 
> No warnings, post core

There are many things Sans misses regarding his old partner.

Gaster was a fool and a dork, but they were typically like-minded, and they could talk for hours on end about String Theory, Schrödinger's cat, or other quantum physics related nonsense and never run out of steam. He misses those conversations, the way it felt as if their brains moved on the same wavelength. Even on the off chance they disagreed about a subject, it was exhilarating trying to prove the other wrong. He can still remember spending hours in the local library, combing through old tomes in hopes of finding evidence that would turn the tides in his favor.

(Gaster, of course, would be sitting on the other side of the table, a stack of books in front of him so tall that it nearly hid him from view. They would sneak glances at each other every few minutes, wondering if their opposition found something useful yet.)

His partner was a professional while working. He was meticulous in his planning, precise when it came to experimentation. He made sure to write down everything step by step, first from a scientific standpoint, then in simpler terms. His systems were outlandish in Sans' opinion, and they had often fought in the beginning about the way a proper lab should be run. Sans misses the way they would happen to bump shoulders often and share a secret smile, even though they had a spacious room all to themselves. He misses how flustered Gaster got when Sans sneaked him a kiss during work hours, and how he would be scolded for acting so childishly. Though Gaster's words bit, Sans could always see the spark of joy in his eyes, and the scientist would apologize for speaking so harshly later.

(They had eventually decided on having a ten minute breaks occasionally throughout the day, and they would somehow always manage to take off during at the same time. They would leave the building to find the nearest Nice Cream stand and share a cone in the sweltering heat, flushed with nervousness at such an intimate act.)

Gaster’s fingers were long, sculpted bones that had captured Sans’ envy the first time they met. His own phalanges were nubs, short just like the rest of him, and he had originally been bitter with the way his colleagues treated him due to his height. Gaster had always given Sans the respect he deserved, but it had taken a while for him to realize that, regrettably. Anyway, fingers. Beautiful bone white fingers, the kind that would have been perfect for piano playing. Gaster’s way of communication involved the use of his hands, and it had been quite an uphill climb trying to understand him at first. Sans had often complained that his partner was moving too fast, or that it was silly for him to learn a new language just to speak with one guy, but in truth he always got distracted watching them flutter, mesmerized at how elegant they were.

(Sometimes he got distracted watching Gaster flip a page in a book or twirl a pencil with his fingers. He’d nearly started a fire more than once because of this, his attention too focused on them instead of the Bunsen burner in front of him. He’d laugh it off later, but the occurrences were too frequent for him to ignore the situation at hand.)

(He misses those fingers, and the way Gaster would join their hands together when they went for walks. It always felt awkward because they were so mismatched, but it warmed his heart none the less. He misses how Gaster would casually pat him on the head or caress his cheek when they cuddled in front of the TV, watching reruns of their favorite shows, sharing innocent kisses during the commercials.)

Once they had become more than just partners, they had been closer than peas in a pod. Sure, there were the bad times, the harsh arguments, and the days spent avoiding each other, but there was also the good times. Sans misses the time they shared together, the moments they spent giggling at bad puns and science jokes or reading scientific articles to each other. They used to pretend that the “”puzzles”” in the Core and Hotland were arcade games, and they would spend hours huddled over new level designs, much to the displeasure of the other workers.

(Sans can still recall the day they took a trip to Snowdin to check out a house that was on the market. The town was aptly named, and since neither of them though to dress warmly, they huddled together, the steam rising from their breath mixing. The house had been just what they wanted, it was affordable and spacious enough for the two of them. Later on, if they chose to settle down in it, it would be possible for them to get an addition for a personal lab to research outside of work.)

(They had loved it, and fully intended on buying it.)

(Gaster’s accident happened before all the papers could be signed.)

(Sans went through with the transaction anyway. Every time he entered the house after that, there was an unsettling chill in the air. He misses the warmth he felt whenever he was near Gaster.)

And now, as he lies alone in his room, or says bad puns to the woman behind the door, or looks after his younger brother, he can’t bring himself to forget all that he’s lost.

(Above all, Sans misses Gaster)

**Author's Note:**

> Please kudos/comment if you enjoyed, it'd mean a lot to me
> 
> If you have a problem with my style or see an error, don't hesitate to say something. If you have any requests, shoot me a message :3


End file.
